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1.
Health Promot Pract ; : 15248399241258725, 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38859686

ABSTRACT

The COVID-19 pandemic placed significant burden on public health professionals, with many experiencing burnout and leaving the profession. The New York State Public Health Association (NYSPHA) recognized the impact of the pandemic on the state's public health workforce and sought professional development opportunities to support current and future generations of public health professionals. To achieve this goal, NYSPHA solicited input from its members and potential members via survey and focus groups as part of its New Directions Initiative. Seventy individuals participated in listening sessions, and 850 responded to the survey. While more than half felt that NYSPHA is invested in the health and wellness of New Yorkers, fewer considered NYSPHA a leader in public health or a go-to source for public health information. Only about one-third felt connected to NYSPHA as a public health professional. Participants identified multiple professional development opportunities that would encourage them to join or renew their membership including sections or special interest groups (57.4%), opportunities to gain leadership experience (56.7%), volunteering (58.1%), a new committee that addresses public health in the community (55.9%), and mentorship (48.4%). NYSPHA used the results of the survey and focus groups to provide several professional development opportunities including a mentorship program, a new Public Health in Action Committee, and special interest groups in mental health and climate change that have already made a difference in local New York State communities. Similar organizations may use NYSPHA's experience as an example for supporting their workforce to maximize impact on the communities they serve.

2.
Community Ment Health J ; 60(5): 859-868, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38374308

ABSTRACT

Deaths by overdose and suicide have been steadily rising, yet efforts to jointly address them have been limited despite shared risk and protective factors. The purpose of this study was to explore ways of jointly addressing these two significant public health issues at the community level. To accomplish this goal, we distributed an electronic survey via email to all 58 Local Mental Hygiene Directors (LMHDs) and 184 substance use and 57 suicide prevention coalition leads in New York State in March 2019 to better understand attitudes, perceptions, and practice of community-based overdose and suicide prevention. A total of 140 unique individuals completed the survey for a 47% usable response rate. Participants overwhelmingly reported that suicide and overdose are preventable and that individuals with risky substance use would benefit most from suicide prevention services compared to other populations. In addition, substance use prevention coalition leads reported less awareness of key suicide prevention programs than suicide prevention coalition leads and LMHDs; LMHDs were generally most familiar with suicide prevention programs. Finally, substance use and suicide prevention coalition leads were interested in collaborating to raise awareness, provide training, and implement community-based activities. These findings demonstrate a consensus among county leadership and substance use and suicide prevention coalition leads that suicide and overdose are prevalent in their communities and that increased collaboration to address these two public health issues is warranted. Results suggest a need for education, training, and technical assistance to support collaboration.


Subject(s)
Drug Overdose , Leadership , Suicide Prevention , Humans , New York , Drug Overdose/prevention & control , Female , Male , Surveys and Questionnaires , Adult , Suicide/psychology , Middle Aged , Health Knowledge, Attitudes, Practice , Community Mental Health Services/organization & administration , Substance-Related Disorders/prevention & control
3.
Foot Ankle Int ; 45(5): 467-473, 2024 May.
Article in English | MEDLINE | ID: mdl-38400716

ABSTRACT

BACKGROUND: Open fractures of the talar body and neck are uncommon. Previous reports of associated deep infection rates and resulting surgical requirements vary widely. The primary objective of this study is to report the incidence of deep infections for isolated open talar body and neck fractures, and secondarily the incidence and number of total surgeries performed (TSP), secondary salvage procedures (SSPs), and nonsalvage procedures (NSPs). METHODS: Retrospective case-control study of 32 consecutive isolated open talus fracture patients (22 neck, 10 body) were followed for an average of 39.2 months. RESULTS: Five (15.6%) fractures developed deep infections. Fifty percent of open body fractures became infected compared with 0% of neck fractures (P < .001). There was no difference between infected group (IG) and uninfected fracture group (UG) with respect to age, sex, body mass index, tobacco, diabetes, vascular disease, open fracture type, wound location, hours to irrigation and debridement, or definitive treatment. The majority (92.6%) of UG fractures used a dual incision with open wound extension. There were more single extensile approaches in the IG group (P = .04). The IG required 5.8 TSP per patient compared with 2.1 in the UG (P = .004). All (100%) of the IG required an SSP compared with 29.6% of the UG (P = .006). All (100%) of the IG required an NSP compared to 40.7% of the UG (P = .043). In the IG, 2.8 NSPs per patient were required after definitive surgery compared with 1.18 in the UG (P = .003). Of those followed 1 year, the incidence of SSP remained higher in the IG (P = .016). CONCLUSION: The incidence of deep infection following isolated open talar fractures is high and occurs disproportionally in body fractures. Infected fractures required nearly 6 surgeries, and all required SSP. LEVEL OF EVIDENCE: Level IV, prognostic.


Subject(s)
Fractures, Open , Surgical Wound Infection , Talus , Humans , Retrospective Studies , Talus/injuries , Talus/surgery , Surgical Wound Infection/epidemiology , Surgical Wound Infection/etiology , Case-Control Studies , Adult , Male , Female , Fractures, Open/surgery , Fractures, Open/complications , Middle Aged , Incidence , Debridement , Fracture Fixation, Internal/adverse effects , Fracture Fixation, Internal/methods , Aged , Young Adult
4.
Community Ment Health J ; 60(1): 191-199, 2024 01.
Article in English | MEDLINE | ID: mdl-37351714

ABSTRACT

Mental health and suicide are serious concerns in the U.S. Though many adults report struggling with their mental health, a significant proportion do not receive care for various reasons including stigma, limited availability, long wait times, inability to pay, and a lack of culturally appropriate options. Helplines can be used to fill gaps in care and, though currently underutilized, are a significant focus of the federal government in the implementation of 988. To better understand the factors that facilitate and impede the utilization of helplines, we conducted 14 focus groups with 95 college students attending a public university and two private colleges in upstate New York between April 2019 and October 2020. Participants included undergraduates, graduate students, LGBTQIA + students, student-athletes, and international students. Participants shared several reasons for using helplines including convenience, comfort, immediate support, and privacy and anonymity. On the other hand, participants expressed hesitation as they expected ingenuine interactions with operators and a lack of continuity, they feared police involvement, and they felt that helplines are not for them, as they are marketed for those in a mental health or suicide crisis and their issues are not that severe. LGBTQIA + participants provided additional reasons as to why they use and do not use LGBTQIA+-specific helplines. Together, our findings suggest the need for improved education, marketing, and training around helplines and may be used to inform the implementation and promotion of 988 in its early stages.


Subject(s)
Mental Health , Suicide , Adult , Humans , New York , Students/psychology , Emotions
5.
J Behav Health Serv Res ; 49(2): 252-258, 2022 04.
Article in English | MEDLINE | ID: mdl-35028872

ABSTRACT

Mental health has long been a challenge on college and university campuses. Though it has historically taken a back seat to physical health, college administrators recently identified mental health as a key area for additional support. With the COVID-19 pandemic bringing mental health into the conversation across the country, there is no more critical and opportune time for colleges and universities to prioritize mental health. Many public and private universities alike have begun to do this, but how can they ensure that the services and resources they are providing and promoting get used and that students, faculty, and staff reap the benefits of these efforts? This commentary describes a set of universal steps the authors recommend based on their experience working with colleges and universities across New York State to increase uptake and usage of services.


Subject(s)
COVID-19 , Mental Health , COVID-19/epidemiology , Humans , Pandemics , Students , Universities
6.
J Subst Abuse Treat ; 126: 108330, 2021 07.
Article in English | MEDLINE | ID: mdl-34116821

ABSTRACT

BACKGROUND: Despite prevention and treatment efforts, opioid overdose deaths continue to rise in the United States and totaled 46,802 in 2018. This public health crisis is closely linked with suicide, with those who misuse opioids at six times the risk of death by suicide. Suicide prevention in substance use disorder (SUD) treatment may be a critical step in saving lives and promoting recovery among those at risk for opioid overdose. METHODS: We distributed an electronic survey to clinicians in mental health and SUD treatment in nine health systems across New York State from November 2018 to January 2019. The goal of the survey was to assess attitudes, perceptions, practice, and training needs among SUD treatment providers and how they differ from those of mental health providers. RESULTS: A total of 633 clinicians responded to the survey (62.4% response rate). Seventy-one percent of SUD providers reported working with a client who attempted suicide. Even so, less than half of SUD providers reported routinely screening new (48.9%) or existing patients (25.6%) for suicidal thoughts/behaviors; overall, 28.4% of SUD providers reported low levels of action to address suicide risk, compared to 9.0% of mental health providers (p < 0.001). Perceived self-efficacy and effectiveness at reducing a patient's risk of suicide and training completion were strongly associated with routine delivery of suicide safer care in adjusted logistic regression models. CONCLUSIONS: The results of this study identify key areas for targeted training and technical assistance to increase the provision of quality suicide safer care in SUD treatment.


Subject(s)
Mental Health , Substance-Related Disorders , Humans , New York , Perception , Suicidal Ideation , United States
7.
Prev Med ; 148: 106572, 2021 07.
Article in English | MEDLINE | ID: mdl-33894231

ABSTRACT

Deaths from overdose have risen dramatically over the past decade, driven mainly by opioids. In response, the Centers for Disease Control and Prevention released guidance on safe prescribing, safe storage of medications, Medication-Assisted Treatment (MAT), and the use of Naloxone to reverse an overdose. Even with this guidance, overdose deaths continue to rise. Suicide prevention is a strategy that may help address this problem. Suicide rose 32.4% between 1999 and 2019, from 10.5 to 13.9 per 100,000. Closely linked to overdose, the suicide rate among those with opioid use disorder is 87 per 100,000 population, six times that of the general US population. With multiple shared individual-level risk factors, strict standards for case ascertainment, and high potential for misclassification of opioid suicides, the distinction between overdose and suicide is often unclear, and the number of suicides is likely underestimated. The Surgeon General recently released a call to action for a public health approach to suicide prevention. Primary care and emergency departments have a major role to play. This commentary describes suicide as a hidden contributor to the opioid crisis; the rationale for integration of suicide prevention in primary care and emergency departments; and screening, education, brief intervention, and follow up and monitoring techniques that these settings can employ. Done effectively, this strategy has the potential to save countless lives.


Subject(s)
Drug Overdose , Emergency Medicine , Opioid-Related Disorders , Suicide Prevention , Analgesics, Opioid/adverse effects , Drug Overdose/drug therapy , Humans , Naloxone/therapeutic use , Opioid Epidemic , Opioid-Related Disorders/epidemiology , Primary Health Care
8.
Sci Rep ; 9(1): 14737, 2019 Oct 14.
Article in English | MEDLINE | ID: mdl-31611564

ABSTRACT

Seismic and electromagnetic methods are fundamental to Solid Earth research and subsurface exploration. Acquisition cost reduction is making dense 3D application of these methods accessible to a broad range of geo-scientists. However, the challenge of extracting geological meaning remains. We develop the concept of "textural domaining" for 3D seismic reflectivity data. Dip-steered seismic texture attributes are combined with unsupervised learning to generate sets of volume rendered images accompanied by a seismic texture reference diagram. These methods have the potential to reveal geological and geotechnical properties that would otherwise remain hidden. Analysis of seismic texture presents particular value in hard-rock settings where changes in velocity may be negligible across rock volumes exhibiting significant changes in rock mass texture. We demonstrate application and value of textural domaining with three industry-scale field examples. The first example links seismic texture to rock type along a 400 km long transect through central Australia. The second and third examples partition dense 3D seismic data based on texture for complex hard rock terrains in Nevada, USA and Kevitsa, Finland. Finally, we demonstrate application of domaining within texture guided cooperative inversion of 3D seismic reflectivity and magnetotelluric data to provide new perspectives on Solid Earth geology.

9.
J Behav Health Serv Res ; 44(1): 168-176, 2017 Jan.
Article in English | MEDLINE | ID: mdl-26276420

ABSTRACT

This report presents results of Project LINK, a Substance Abuse and Mental Health Services Administration (SAMHSA)-funded, 5-year collaboration (2007-2012) between New York City (NYC) health and NY State substance abuse disorder (SUD) agencies, an LGBT organization contractor, and multiple SUD, social service, and mental health referral agencies. LINK allowed the first ever SUD screening, brief intervention, and referrals to treatment (SBIRT) intervention services onsite in NYC Bureau of Sexually Transmitted Disease Control (BSTDC) clinics. Factors favoring collaboration were (a) joint recognition of substance abuse as an STD risk factor; (b) prior collaborations; (c) agreement on priority of BSTDC's mission and policies; (d) extensive SBIRT training, cross training on STDs; (e) a memorandum of agreement; and (f) mutual transparency of collaborative efforts, among others. LINK screened over 151,000 STD clinic patients and delivered brief interventions to 60% of positively screened patients and met a mandated follow-up target. Factors found to facilitate collaboration here may help screen prospective new health collaborations.


Subject(s)
Ambulatory Care Facilities , Cooperative Behavior , Program Development , Sexually Transmitted Diseases , Substance-Related Disorders/therapy , Humans , Leadership , New York City , Prospective Studies , Referral and Consultation , Sexual and Gender Minorities
10.
Prev Med ; 91: 397-399, 2016 10.
Article in English | MEDLINE | ID: mdl-27544318

ABSTRACT

Overdose deaths from heroin and prescription opioids have reached epidemic proportions in recent years. Deaths specifically involving heroin have more than tripled since 2011, and for the first time, drug overdose deaths have exceeded deaths resulting from motor vehicle accidents. This epidemic has been receiving attention among policymakers and the media which has resulted in efforts to provide training and education on prescribing practices, increase the use of naloxone, and expand the availability and use of Medication-Assisted Treatment (MAT). What is not being talked about is the relationship between early initiation of less harmful substances such as alcohol and marijuana and subsequent use of prescription opioids and heroin. Screening, Brief Intervention, and Referral to Treatment (SBIRT) is a model which shows promise for preventing initiation and reducing risky substance use among adolescents before it progresses to use of harder drugs such as heroin. Unfortunately, though recommended by the American Academy of Pediatrics, health care providers are not even screening their adolescent patients for substance use. The heroin and prescription opioid epidemic and the dissemination of information regarding federal, state, and local efforts to combat the epidemic provide a platform for increasing awareness of SBIRT, garnering support for more research, and facilitating uptake and integration into practice. It is time to add SBIRT to the conversation.


Subject(s)
Analgesics, Opioid/adverse effects , Drug Overdose/epidemiology , Epidemics , Heroin/adverse effects , Referral and Consultation , Adolescent , Adolescent Health Services , Drug Overdose/drug therapy , Humans , Pediatrics , Substance-Related Disorders/diagnosis , Substance-Related Disorders/therapy
11.
Subst Abus ; 37(4): 511-515, 2016.
Article in English | MEDLINE | ID: mdl-27070491

ABSTRACT

BACKGROUND: School-based health centers (SBHCs) are satellite primary care clinics conveniently located within high-risk schools. Providing screening, brief intervention, and referral to treatment (SBIRT) in SBHCs has the potential to greatly increase identification and intervention among adolescents with problem substance use. Nevertheless, only 11% of New York State SBHC providers report the use of SBIRT. This study identifies strategies for communicating about SBIRT with the goal of raising awareness and promoting voluntary adoption and implementation among both SBHC program directors and clinicians. METHODS: All 162 New York State SBHC program directors and clinicians serving middle and high school students were surveyed between May and June 2013 (40% response rate). Program directors were asked which factors were most important to them in their decision to adopt new practices, and both program directors and clinicians were asked to rank-order statements in 2 categories: (1) Substance use and its effects and (2) SBIRT integration and outcomes. RESULTS: Student need was valued far more than any other factor in program directors' decisions to adopt new practices. Both program directors and clinicians perceived the association between substance use and risky sexual behavior and the benefits and cost-effectiveness of SBIRT compared with other preventive health screenings as the strongest motivators to adopt and implement SBIRT. CONCLUSIONS: Findings from this study suggest that SBIRT awareness-raising strategies present the cost-effectiveness of SBIRT, highlight student need, particularly the connection between substance use and risky sexual behaviors, and should be communicated by state health departments and professional organizations.


Subject(s)
Attitude of Health Personnel , Health Knowledge, Attitudes, Practice , Health Promotion/methods , Referral and Consultation , School Health Services , Substance-Related Disorders/diagnosis , Substance-Related Disorders/therapy , Adult , Female , Humans , Male , Middle Aged , New York
12.
J Sch Health ; 86(2): 96-104, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26762820

ABSTRACT

BACKGROUND: Adolescent substance use is associated with chronic health conditions, accidents, injury, and school-related problems, including dropping out. Schools have the potential to provide students with substance use prevention and intervention services, albeit with confidentiality challenges. School-based health centers (SBHCs) provide confidentiality, positioning them as ideal settings to provide substance use prevention and intervention. This study identified program directors' and clinicians' barriers to addressing adolescent substance use in SBHCs. METHODS: Between May and June 2013, an electronic survey was distributed to all 162 New York State SBHC program directors and clinicians serving middle and high school students. RESULTS: The most prevalent perceived barriers to discussing substance use with students were time constraints (43%), the belief that students are not honest about their use (43%), and clinicians' lack of training (28%). Both directors and clinicians identified challenges in getting students to return for additional sessions to address their use, and they also indicated that confidentiality was a treatment referral barrier. CONCLUSIONS: This study identified timely opportunities that may be leveraged and unique challenges that may be overcome with targeted dissemination, training, and technical assistance efforts to enable directors and clinicians to routinely address substance use in SBHCs.


Subject(s)
Health Knowledge, Attitudes, Practice , Health Services Accessibility , Referral and Consultation , School Health Services , Substance-Related Disorders , Adolescent , Adolescent Behavior , Adolescent Health Services , Adult , Aged , Faculty , Female , Health Services Needs and Demand , Health Surveys , Humans , Male , Middle Aged , New York , Perception , Referral and Consultation/statistics & numerical data , Schools , Substance-Related Disorders/prevention & control , Substance-Related Disorders/psychology , Substance-Related Disorders/therapy , Young Adult
13.
Am J Drug Alcohol Abuse ; 42(1): 32-8, 2016.
Article in English | MEDLINE | ID: mdl-26555138

ABSTRACT

OBJECTIVE: This article reports the integration and outcomes of implementing intervention services for substance use disorder (SUD) in three New York City public sexually transmitted disease (STD) clinics. METHODS: The screening, brief intervention, and referral to treatment (SBIRT) service model was implemented in the STD clinics in 2008. A relational database was developed, which included screening results, service dispositions, face-to-face interviews with 6-month follow-ups, and treatment information. RESULTS: From February 2008 to the end of September 2012, 146,657 STD clinic patients 18 years or older were screened for current or past substance use disorders; 15,687 received a brief intervention; 954 received referrals to formal substance abuse treatment; 2082 were referred to substance abuse support services such as Alcoholics Anonymous (AA), and 690 were referred to mental health, social or HIV awareness services. Intervention services delivered through SBIRT resulted in improvements in multiple outcomes at 6 month follow-up. Patients who received interventions had reduced SUD risks, fewer mental health problems, and fewer unprotected sexual contacts. CONCLUSION: Delivery of SUD services in a public health setting represents a significant policy and practice change and benefits many individuals whose SUDs might otherwise be overlooked. Intervention services for substance use disorder were integrated and highly utilized in the STD setting. Further research needs to focus on the long-term impact of SUD interventions in the STD setting, their cost effectiveness, and the extent they are financially sustainable under the new healthcare law.


Subject(s)
Ambulatory Care Facilities/organization & administration , Sexually Transmitted Diseases/prevention & control , Substance-Related Disorders/therapy , Adolescent , Adult , Female , Health Services Accessibility , Humans , Male , Middle Aged , New York City , Young Adult
14.
Subst Abus ; 37(1): 161-7, 2016.
Article in English | MEDLINE | ID: mdl-25774987

ABSTRACT

BACKGROUND: Screening, brief intervention, and referral to treatment (SBIRT) has been endorsed by the American Academy of Pediatrics as an evidence-based strategy to address risky substance use among adolescents in primary care. However, less than half of pediatricians even screen adolescents for substance use. The purpose of this study was to identify variation in SBIRT practice and explore how program directors' and clinicians' attitudes and perceptions of effectiveness, role responsibility, and self-efficacy impact SBIRT adoption, implementation, and practice in school-based health centers (SBHCs). METHODS: All 162 New York State SBHC program directors and clinicians serving middle and high school students were surveyed between May and June of 2013 (40% response rate). RESULTS: Only 22% of participants reported practicing the SBIRT model. Of the individual SBIRT model components, using a standardized tool to screen students for risky substance use, referring students with substance use problems to specialty treatment, and assessing students' readiness to change were practiced least frequently. Less than 30% of participants felt they could be effective at helping students reduce substance use, 63% did not believe it was their role to use a standardized screening tool, and 20-30% did not feel confident performing specific aspects of intervention and management. Each of these factors was correlated with SBIRT practice frequency (P < .05). CONCLUSIONS: Findings from this study identify an important gap between an evidence-based SBIRT model and its adoption into practice within SBHCs, indicating a need for dissemination strategies targeting role responsibility, self-efficacy, and clinicians' perceptions of SBIRT effectiveness.


Subject(s)
Health Knowledge, Attitudes, Practice , Health Personnel/psychology , Psychotherapy, Brief , Referral and Consultation , School Health Services , Substance-Related Disorders/diagnosis , Substance-Related Disorders/therapy , Adolescent , Adolescent Health Services , Adult , Aged , Evidence-Based Practice , Female , Humans , Male , Middle Aged , New York , Young Adult
15.
J Mol Cell Cardiol ; 88: 1-13, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26386426

ABSTRACT

Gap junctions (GJ) are intercellular channels composed of connexin subunits that play a critical role in a diverse number of cellular processes in all tissue types. In the heart, GJs mediate electrical coupling between cardiomyocytes and display mislocalization and/or downregulation in cardiac disease (a process known as GJ remodeling), producing an arrhythmogenic substrate. The main constituent of GJs in the ventricular myocardium is Connexin 43 (Cx43), an integral membrane protein that is rapidly turned over and shows decreased expression or function with age. We hypothesized that Wwp1, an ubiquitin ligase whose expression in known to increase in aging-related pathologies, may regulate Cx43 in vivo by targeting it for ubiquitylation and degradation and yield tissue-specific Cx43 loss of function phenotypes. When Wwp1 was globally overexpressed in mice under the control of a ß-actin promoter, the highest induction of Wwp1 expression was observed in the heart which was associated with a 90% reduction in cardiac Cx43 protein levels, left ventricular hypertrophy (LVH), and the development of lethal ventricular arrhythmias around 8weeks of age. This phenotype was completely penetrant in two independent founder lines. Cardiomyocyte-specific overexpression of Wwp1 confirmed that this phenotype was cell autonomous and delineated Cx43-dependent and -independent roles for Wwp1 in arrhythmogenesis and LVH, respectively. Using a cell-based system, it was determined that Wwp1 co-immunoprecipitates with and ubiquitylates Cx43, causing a decrease in the steady state levels of Cx43 protein. These findings offer new mechanistic insights into the regulation of Cx43 which may be exploitable in various gap junctionopathies.


Subject(s)
Arrhythmias, Cardiac/genetics , Connexin 43/genetics , Hypertrophy, Left Ventricular/genetics , Myocytes, Cardiac/metabolism , Ubiquitin-Protein Ligases/genetics , Actins/genetics , Actins/metabolism , Animals , Arrhythmias, Cardiac/metabolism , Arrhythmias, Cardiac/pathology , Connexin 43/metabolism , Disease Models, Animal , Female , Gap Junctions/metabolism , Gap Junctions/pathology , Gene Expression Regulation , Heart Ventricles/metabolism , Heart Ventricles/pathology , Hypertrophy, Left Ventricular/metabolism , Hypertrophy, Left Ventricular/pathology , Male , Mice , Mice, Transgenic , Myocardium/metabolism , Myocardium/pathology , Myocytes, Cardiac/pathology , Phenotype , Promoter Regions, Genetic , Proteasome Endopeptidase Complex/metabolism , Protein Stability , Proteolysis , Signal Transduction , Ubiquitin-Protein Ligases/metabolism , Ubiquitination
16.
J Contam Hydrol ; 181: 161-71, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26141344

ABSTRACT

The release and retention of in-situ colloids in aquifers play an important role in the sustainable operation of managed aquifer recharge (MAR) schemes. The processes of colloid release, retention, and associated permeability changes in consolidated aquifer sediments were studied by displacing native groundwater with reverse osmosis-treated (RO) water at various flow velocities. Significant amounts of colloid release occurred when: (i) the native groundwater was displaced by RO-water with a low ionic strength (IS), and (ii) the flow velocity was increased in a stepwise manner. The amount of colloid release and associated permeability reduction upon RO-water injection depended on the initial clay content of the core. The concentration of released colloids was relatively low and the permeability reduction was negligible for the core sample with a low clay content of about 1.3%. In contrast, core samples with about 6 and 7.5% clay content exhibited: (i) close to two orders of magnitude increase in effluent colloid concentration and (ii) more than 65% permeability reduction. Incremental improvement in the core permeability was achieved when the flow velocity increased, whereas a short flow interruption provided a considerable increase in the core permeability. This dependence of colloid release and permeability changes on flow velocity and colloid concentration was consistent with colloid retention and release at pore constrictions due to the mechanism of hydrodynamic bridging. A mathematical model was formulated to describe the processes of colloid release, transport, retention at pore constrictions, and subsequent permeability changes. Our experimental and modeling results indicated that only a small fraction of the in-situ colloids was released for any given change in the IS or flow velocity. Comparison of the fitted and experimentally measured effluent colloid concentrations and associated changes in the core permeability showed good agreement, indicating that the essential physics were accurately captured by the model.


Subject(s)
Colloids , Groundwater , Models, Theoretical , Aluminum Silicates , Clay , Groundwater/analysis , Groundwater/chemistry , Hydrodynamics , Hydrology/methods , Osmolar Concentration , Osmosis , Permeability , Porosity , Solutions , Water
17.
Radiology ; 275(1): 80-8, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25393848

ABSTRACT

PURPOSE: To assess the accuracy of computed tomographic (CT) examinations performed for the purpose of transcatheter aortic valve replacement (TAVR) planning to diagnose obstructive coronary artery disease (CAD). MATERIALS AND METHODS: With institutional review board approval, waivers of informed consent, and in compliance with HIPAA, 100 consecutive TAVR candidates (61 men, mean age 79.6 years ± 9.9) who underwent both TAVR planning CT (with a dual-source CT system) and coronary catheter (CC) angiographic imaging were retrospectively analyzed. At both modalities, the presence of stenosis in the native coronary arteries was assessed. Additionally, all coronary bypass grafts were rated as patent or occluded. With CC angiographic imaging as the reference standard, the accuracy of CT for lesion detection on a per-vessel and per-patient basis was calculated. The accuracy of CT for the assessment of graft patency was also analyzed. RESULTS: For per-vessel and per-patient analysis for the detection of stenosis that was 50% or more in the native coronary arteries, CT imaging had, respectively, 94.4% and 98.6% sensitivity, 68.4% and 55.6% specificity, 94.7% and 93.8% negative predictive value (NPV), and 67.0% and 85.7% positive predictive value. Per-patient sensitivity of stenosis 50% or greater with CT for greater than 70% stenosis at CC angiographic imaging was 100%. All 12 vessels in which percutaneous coronary intervention was performed were correctly identified as demonstrating stenosis 50% or greater with CT. There was agreement between CT and CC angiographic imaging regarding graft patency in 114 of 115 grafts identified with CC angiographic imaging. CONCLUSION: TAVR planning CT has high sensitivity and NPV in excluding obstructive CAD. An additional preprocedural CC angiographic examination may not be required in TAVR candidates with a CT examination that does not show obstructive CAD.


Subject(s)
Coronary Artery Disease/diagnostic imaging , Tomography, X-Ray Computed/methods , Transcatheter Aortic Valve Replacement , Aged , Aged, 80 and over , Cardiac-Gated Imaging Techniques , Contrast Media , Coronary Angiography , Coronary Artery Disease/surgery , Female , Humans , Male , Patient Care Planning , Radiographic Image Interpretation, Computer-Assisted , Retrospective Studies , Risk Factors , Triiodobenzoic Acids , Vascular Patency
20.
AJR Am J Roentgenol ; 203(1): W70-7, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24951230

ABSTRACT

OBJECTIVE: The purpose of this article is to prospectively determine the value of stress dual-energy CT (DECT) myocardial perfusion imaging to coronary CT angiography (CTA) for the assessment of coronary artery disease (CAD) in a high-risk population. SUBJECTS AND METHODS: We prospectively enrolled 29 consecutive patients who were referred for cardiac SPECT examinations for known or suspected CAD to also undergo pharmacologic stress cardiac DECT. In 25 patients, cardiac catheterization was available as the reference standard for morphologically significant stenosis. The performance of coronary CTA alone, DECT myocardial perfusion alone, and the combination of both was assessed by calculating sensitivity, specificity, and AUC values. RESULTS: For morphologically significant stenosis, coronary CTA alone and myocardial DECT assessment alone had 95% sensitivity and 50% specificity. The combined approach yielded 100% sensitivity and 33% specificity if either was positive and 90% sensitivity and 67% specificity if both were positive. The AUC value was highest (0.78) if both were positive. For hemodynamically significant lesions, coronary CTA alone had 91% sensitivity and 38% specificity, and DECT alone had 95% sensitivity and 75% specificity. The combined approach yielded 100% sensitivity and 38% specificity if either was positive and 86% sensitivity and 75% specificity if both were positive. AUC values were highest for DECT alone (0.85) and the "both positive" evaluation (0.80). CONCLUSION: The combined analysis of coronary CTA and DECT myocardial perfusion reduces the number of false-positives in a high-risk population for CAD and outperforms the purely anatomic test of coronary CTA alone for the detection of morphologically and hemodynamically significant CAD.


Subject(s)
Coronary Angiography , Coronary Artery Disease/diagnostic imaging , Exercise Test/methods , Tomography, Emission-Computed, Single-Photon , Tomography, X-Ray Computed , Adenosine , Cardiac Catheterization , Cardiac-Gated Imaging Techniques , Contrast Media , Female , Humans , Iopamidol , Male , Middle Aged , Prospective Studies , Purines/administration & dosage , Pyrazoles/administration & dosage , Radiation Dosage , Radiographic Image Interpretation, Computer-Assisted , Sensitivity and Specificity
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